• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.173-176
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• 2000

The fact that the channel coding methode with property of the source coder is better than using the channel characteristics is well known. In this paper We propose the UEP channel coding scheme using IP-SCCC and DCT-based embedded coder for image transmission. Moreover, to evaluate the effectiveness of the proposed scheme some simulation results are presented, in which the channel models of additive white Gaussian noise and Rayleigh fading are assumed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.7
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• pp.398-400
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• 2014

In this letter, we propose a cross-layer technique jointly considering modulation coding schemes (MCSs) of medium access control (MAC) layer, source significance information (SSI) and error concealment unit of application (APP) layer, and channel quality information (CQI) of physical (PHY) layer. We demonstrate the improved video quality by the proposed technique when H.264 videos are streamed over Rayleigh fading wireless channels.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.2052-2055
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• 2003

본 논문은 MDC의 전송 중 발생한 에러를 검출하고, 그 에러를 정정하는 알고리즘을 제안한다. 이 알고리즘은 기존의 MDC 와 같이 약간의 redundancy를 가지는 두 개의 sub-bitstream 을 생성하는데, 한쪽 sub-bitstream에 에러가 발생하였을 때, 다른 한쪽의 sub-bitstream을 이용하여, 발생한 비트 에러를 정정한다. 제안된 알고리즘에 대한 BER-SNR실험은 Generalized Gaussian source를 임의적으로 발생시켜서 결과를 얻어내었다. sub-bitstream에서 에러가 발생하였을 때 우리가 제안한 알고리즘은 BER<10/sup -3/에서 기존 알고리즘보다 약 12㏈ 높은 성능을 얻을 수 있었다.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1582-1585
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• 2002

In recent years the demand for digital video and image communications has been increased tremendously. On the other hand, video communications requires very much bandwidth in comparison with other information types such as text and data. Thus to adapt with the bandwidth-limited channels, especially wireless channels, video source must be compressed extremely. A new video coding standard namely H.26L is being developed by Joint Video Team (JVT). In this paper performance of H.26L is analyzed in an AWGN environment.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.2
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• pp.243-250
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• 2013

We have entered into an era of smart software system where the many kinds of embedded software, especially SCADA and Automotive software not only require high reliability and safety but also high-security. Removing software weakness during the software development lifecycle is very important because hackers exploit weaknesses which are source of software vulnerabilities when attacking a system. Therefore the coding rule as like core functions of MISRA-C should expand their coding focus on security. In this paper, we used CERT-C secure coding rules for nuclear-related software being developed to demonstrate high-safety software, and proposed how to remove software weakness during development.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.5
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• pp.1013-1027
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• 2011

In this paper we propose ATCS, a practical TCP protocol coding scheme based on network coding for satellite IP networks. The proposal is specially designed to enhance TCP performance over satellite networks. In our scheme, the source introduces a degree of redundancy and transmits a random linear combination of TCP packets. Since the redundant packets are utilized to mask packet loss over satellite links, the degree of redundancy is determined by the link error rates. Through a simple and effective method, ATCS estimates link error rates in real time and then dynamically adjusts the redundant factor. Consequently, ATCS is adaptable to a wide range of link error rates by coding TCP segments with a flexible redundancy factor. Furthermore, the scheme is compatible with traditional TCP variants. Simulation results indicate that the proposal improves TCP performance considerably.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.8
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• pp.650-655
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• 2013

For the DC-free encoding of source data, the Guided Scrambling (GS) technique is widely used as multi-mode coding in the optical data storage system. For DC-suppression GS coding in the holographic data storage system, the conservative array and balanced coding criteria are proposed. In this paper, equivalent integer programming models are developed to determine the optimal control bits for the minimum digital sum value (MDSV), conservative array, and balanced coding criteria. Using the proposed integer programming models, we compare the performance of GS encoding for the various combination of control bit/array sizes and scrambling polynomials.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.23-28
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• 2013

In this paper, we propose a simple bidirectional transmission protocol using network coding and digital Fountain codes. In particular, in the proposed scheme, two sources use digital Fountain codes to transmit their message to each other with the help of relays. Then, relays use Fountain codes and network coding to forward the source messages to both sources. To evaluate performance of the proposed protocols, we present the average total throughput over Rayleigh fading channels via Various Monte-Carlo simulations. Results show that the proposed protocol outperforms the two-way relaying transmission protocol without using network coding technique at high SNR region.

• Journal of Broadcast Engineering
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• v.27 no.5
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• pp.773-793
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• 2022

The moving picture experts group (MPEG) immersive video (MIV) coding standard has been established to support six degrees of freedom (6DoF) in virtual reality (VR) by transmitting high-quality multiple immersive videos. The MIV exploits two approaches considering tradeoff between bandwidth and computational complexity: 1) eliminating correlation between multi-view videos or 2) selecting representative videos. This paper presents performance analysis on intermediate synthesized views on source view positions and synthesized pose traces using high-efficiency video coding (HEVC) and versatile video coding (VVC) for above-mentioned two approaches.

• Journal of Broadcast Engineering
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• v.19 no.2
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• pp.174-183
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• 2014

This paper is to propose a scalable video coding scheme for adaptive digital hologram video service for various reconstruction environments. It uses both the light source information and digital hologram at both the sending side and the receiving side. It is a resolution-scalable coding method that scales the resolution, that is, the size of the reconstructed image. The method compresses the residual data for both the digital hologram and the light source information. For the digital hologram, a lossy compression method is used, while for the light source information, a lossless compression method is used. The experimental results showed that the proposed method is superior to the existing method in the image quality at the same compression ratio. Especially it showed better performance than the existing method as the compression ratio becomes higher.